Skip to content
Apply
Stories

Trojan trout: could turning an invasive fish into a ‘super-male’ save a native species?

People in this story

The Guardian, April 2022

On a golden morning in early October, two graduate students from New Mexico State University plunge into the icy current of Leandro Creek. The small waterway flows through the 550,000 acre Vermejo park ranch, a reserve in the Sangre de Cristo Mountains, and the pair are in search of an unusual fish.

Kelsie Field, 25, from the Department of Wildlife and Conservation Ecology, wears a pair of worn grey waders and carries two eight-gallon buckets, one full of water, the other, of scientific gear: test tubes, an electronic scanner and surgical implements. Michael Miller, 30, shoulders a large, waterproof backpack containing a battery attached to an electrode that resembles a metal detector.

Miller dips the “detector” into the creek, squeezing the handle to send approximately 300 volts through the water. While the team’s rubber boots insulate them from the shock, the resident fish are stunned and drift to the surface just long enough for Miller to net them and deposit them in the bucket. Most measure about 10 inches, though some are no larger than a little finger and a few stretch to 16 inches or more.

There are just two species here. One is an embattled native, the Rio Grande cutthroat trout (Oncorhynchus clarki virginalis), distinguished by its cream-coloured skin, mottling of black spots and a vibrant orange slash under the jaw. Once widely distributed in rivers and streams across northern New Mexico and southern Colorado, it is now found across just 10% of its historical range. Today, it is reeling under the pressures of the climate crisis, habitat loss and – in the case of Leandro Creek – a hardy intruder.

Continue reading at the Guardian.

More Stories

Race to deploy AI data centres in space raises safety concerns

03.12.2026
A Palestinian youth collects water at a desalination plant in Khan Younis, southern Gaza Strip, Friday, Feb. 6, 2026. (AP Photo/Abdel Kareem Hana)

Attacks on desalination plants in the Middle East threaten vital freshwater supplies for civilians

03.12.2026
The American black bear (Ursus americanus) is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black bears are omnivores, with their diets varying greatly depending on season and location.

Spotted a bear lately? You’re not alone — why sightings are on the rise

03.13.26
Northeastern Global News